Drowsiness increases slow oscillations in rs-fMRI signal before sleep onset

Ivan Igor Gaez (1) , Elpidio Attoh-Mensah (1) , Clément Nathou (1) , Lydie Vincent (1) , Marc Joliot (2) , Luc Brun (3) , Mikaël Naveau (4) , Olivier Etard (1)

1 COMETE - Mobilités : Vieillissement, Pathologie, Santé
2 IMN - Institut des Maladies Neurodégénératives [Bordeaux]
3 Equipe Image - Laboratoire GREYC - UMR6072
4 Unité Support CYCERON

Sleep can significantly affect the functional MRI (fMRI) signal as reported in previous studies where subjectswere allowed to fall asleep during the examination (Fukunaga et al., 2006, Duyn 2019). Fluctuation in theMRI signal has been associated with the increase in functional connectivity observed during light slow wavesleep (Tagliazucchi et al., 2014). Nevertheless, a major concern arises regarding the limited understandingof the evolution of fMRI signals as a function of drowsiness, when subjects are instructed to remain awake,as typically prescribed in standard resting-state exploration (rs-fMRI). This knowledge gap primarily resultsfrom the challenge of quantifying such vigilance-related events during fMRI, as they mostly occur within thecomplex period of wakefulness-to-sleep transition (Ogilvie, 2001). In this study, we used the percentage ofeye closure (PERCLOS index (Wierwille et al., 1994)) as a proxy of drowsiness to explore its effect on theevolution of the rs-fMRI signal.

Domaines: Sciences du Vivant [q-bio]; Sciences cognitives

Ivan Igor Gaez, Elpidio Attoh-Mensah, Clément Nathou, Lydie Vincent, Marc Joliot, et al.. Drowsiness increases slow oscillations in rs-fMRI signal before sleep onset. OHBM 2024 - the 2024 OHBM Annual Meeting, Organization for Human Brain Mapping, Jun 2024, Seoul, South Korea. ⟨hal-04521091⟩